A conventional cyclone separator, particularly, a cyclone separator used in a vacuum cleaner or the like allows air containing dust sucked by an electric air blower to pass through a dust filter or a dust bag to collect dust in air. However, for a vacuum cleaner using such a cyclone separator, a dust bag needs to be regularly bought and mounted in a vacuum cleaner body, which is inconvenient and troublesome for a user.
To solve such a problem, a vacuum cleaner including a cyclone separator has been proposed that can separate dust from air using a centrifugal force or an inertial force to collect dust without using a dust bag that is a consumable. As a vacuum cleaner including such a cyclone separator, for example, a vacuum cleaner has been proposed in which an outer cyclone and an inner cyclone surrounded by the outer cyclone, which are provided concentrically, communicate with each other in series, thereby increasing dust separation efficiency of the cyclone separator (for example, see Patent Literatures 1 to 3).